It is known that a simple bracket is sufficient to only achieve position control of a component that is to say to prevent displacement of the component relative to another object. To provide vibration isolation of the component a compressible element such as one or more elastomeric or rubber members are normally included as part of a component mount but the inclusion of such a compressible element in a component mount will result in displacement of the component when a load is applied.
In many uses a relatively soft or low stiffness compressible element is desirable to reduce the transmission of vibrations to or from the component but such a soft compressible element will result in unacceptably large displacements of the component when a high load is applied to the component mount.
It is an object of this invention to provide a component mount that provides good vibration isolation when a low load is applied to the component mount and a reduced component displacement when a high load is applied to the component mount.
According to a first aspect of the invention there is provided a component mount comprising a number of attachment members for use in attaching the component mount to a component to be supported and a support structure, a number of compressible load paths between the attachment members and a coupling mechanism wherein the coupling mechanism has a disengaged state in which all the force transmitted through the component mount is transmitted by a first one of the load paths and one or more engaged states in which the first load path and a least one further compressible load path are connected together in parallel by the coupling mechanism and the force transmitted through the component mount is transmitted by the compressible load paths that are acting in parallel.
The component mount may comprise a first attachment member for use in attaching the component mount to a component to be supported, a second attachment member to attach the component mount to a support structure, primary and secondary compressible load paths between the first and second attachment members and a coupling mechanism wherein the coupling mechanism has a disengaged state in which all the force transmitted through the component mount between the first and second attachment members is transmitted by only the primary load path and an engaged state in which the primary and secondary compressible load paths are connected together in parallel by the coupling mechanism between the first and second attachment members and the force transmitted through the component mount between the first and second attachment members is transmitted by both of the compressible load paths acting in parallel.
The primary compressible load path may have a first stiffness, the secondary compressible load path may have a second stiffness and when the coupling mechanism is in the engaged state the resulting stiffness of the connection between the first and second attachment members may be equal the sum of the first stiffness and the second stiffness.
When the coupling mechanism is in the disengaged state the resulting stiffness of the connection between the first and second attachment members may be equal the first stiffness.
One of the first and second attachment members may be a link arm and the other of the first and second attachment members may be a mounting plate.
The mounting plate may form the first attachment member and the link arm may form the second attachment member.
The primary compressible load path may comprise a first compressible member attached at one end to the mounting plate and attached at an opposite end to the link arm and the second compressible load path may comprises a second compressible member attached at one end to the mounting plate and attached at an opposite end to a load transfer member.
The second compressible member may comprise two compressible elements connected in parallel between the mounting plate and the load transfer member.
The coupling mechanism may comprise a slideable coupling member supported by the link arm engageable with an aperture in the load transfer member.
When the coupling member is engaged with the aperture the coupling mechanism may be in the engaged state and when the coupling member is not engaged with the aperture the coupling mechanism may be in the disengaged state.
The primary compressible load path comprises a first compressible member and a third compressible member arranged in series between the first and second attachment members.
One of the first and second attachment members is formed by a first bushing connected to the first compressible member and the other of the first and second attachment members is a second bushing connected to the third compressible member and the first and third compressible members may be connected together by a first link arm having an aperture in each end in which are located the first and second compressible members.
The first bushing may form the first attachment member and the second bushing may form the second attachment member.
The secondary compressible load path may comprise a second compressible member located in an aperture in a second link arm.
The second link arm may be slideably supported by the first link arm.
The coupling mechanism may comprise a slideable coupling member supported by the first link arm engageable with an aperture in the second link arm.
According to a second aspect of the invention there is provided a component mounting system comprising an actuator controlled by an electronic controller and a component mount constructed in accordance with said first aspect of the invention wherein the actuator is operatively connected to the coupling mechanism and the electronic controller is arranged to use the actuator to control the position of the coupling mechanism based upon the level of force predicted to be transferred by the component mount.
The actuator may be operatively connected to the coupling mechanism, the electronic controller may be arranged to use the actuator to position the coupling mechanism in an engaged state when a level of force above a predefined level is predicted to be transferred by the component mount and position the coupling mechanism in a disengaged state when the force predicted to be transferred is below the predefined level.
The predefined level of force is a force that will produce an unacceptable displacement of the component supported by the component mount if the coupling member is in the disengaged state.
The component mount may be a driveline mount of a motor vehicle and a force above the predefined level may be predicted to occur when an engagement state of a transmission forming part of the driveline is changed from a neutral state to an engaged state.
Alternatively, the component mount may be a driveline mount of a motor vehicle and a force above the predefined level may be predicted to occur when gear ratio of a transmission forming part of the driveline is changed from a first ratio to a second ratio.